Question

A. For the reaction 2CH4(g)⇌C2H2(g)+3H2(g) K = 0.140 at 1684 ∘C . What is Kp for the reaction at this temperature? Express your answer numerically.

B.For the reaction

N2(g)+3H2(g)⇌2NH3(g)

Kp = 4.35×10⁻³ at 334 ∘C . What is K for the reaction at this temperature?

Answer 1

1) For the chemical reaction, 2CH_4(g) <-->C₂H_2(g) + 3H_2(g) , K= 0.140 at1684^o C. What is K_p for the reaction at thistemperature?

We know that Kp = Kc * (RT) ^Δn

Where T = Temperature = 1684 oC = 1684 + 273 = 1957K

R = gas constant = 0.0821 L atm / mol - K

Δn = No . of moles of gaseous products - No . of moles ofgaseous reactants

     = (1+3) - 2

     = 2

Plug the values we get Kp = 0.140 * ( 0.0821 * 1957 )²

                                        = 3.614*10 ³

2) For the reaction, N_2(g) + 3H_2(g)<--> 2NH_3(g) , K_p = 4.35 x10^-3 at 334^oC. What is K for the reaction atthis temperature?

We know that Kp = Kc * (RT) ^Δn

Where T = Temperature = 334 o C = 334 + 273 =607K

R = gas constant = 0.0821 L atm / mol - K

Δn = No . of moles of gaseous products - No . of moles ofgaseous reactants

     = 2 - ( 1+3)

     =-2

Plug the values we get K = Kp *  (RT)^-Δn

                                      = 4.35 x 10^-3 * ( 0.0821 *607 ) ²

                                        = 10.80